Bach wrote the cantata during his fourth year in Leipzig, for the 18th Sunday after Trinity. The prescribed readings for the Sunday were from the First Epistle to the Corinthians, Paul's thanks for grace of God in Ephesus, and from the Gospel of Matthew, the Great Commandment. The unknown author of the text concentrated on the love of God in movements 2 to 5 and added one movement about the love of your neighbour in movement 6, continued in the concluding chorale, the third stanza of Martin Luther's "Nun bitten wir den Heiligen Geist". The poet connected the first recitative to the following aria by starting the two thoughts in the recitative by a related line from the aria as a motto, and ending both with the a recapitulation of the first line. The second recitative is a paraphrase of, Elijah lifted to heaven. The second aria is a paraphrase of, which sets the love of God apart from the love of the world. The only other extant cantata for the Sunday is the chorale cantata Herr Christ, der einge Gottessohn, BWV 96, composed in 1724. Like three other cantatas, the early Widerstehe doch der Sünde, BWV 54, and the 1726 works Geist und Seele wird verwirret, BWV 35, and Vergnügte Ruh, beliebte Seelenlust, BWV 170, Bach wrote Gott soll allein mein Herze haben for a single alto soloist, but unlike those works a choir sings the chorale. The three later cantatas, written within a few months, employ the organ as an obbligato instrument, possibly because Bach liked the combination of alto voice and organ registrations. A week later, Bach composed the famous cantata for bass solo, Ich will den Kreuzstab gerne tragen, BWV 56, also concluded by a chorale. It is not known if Bach looked for texts suitable for a solo voice, or if texts were "clerically imposed on him", which stressed individual piety and therefore suggested to be treated as solo cantatas. Bach first performed the cantata on 20 October 1726. It is regarded as part of his third annual cycle of cantatas.
Scoring and structure
The cantata in seven movements is scored for alto, a four-part choir only for the closing chorale, two oboes, taille, two violins, viola, organ obbligato and basso continuo.
As in a number of other works, Bach reused some of his earlier works. The first movement, a sinfonia, and movement 5 rely on a lost concerto, perhaps for oboe or flute, possibly written during his time in Köthen. That same concerto is the source of Bach's Harpsichord Concerto BWV 1053, composed around 1739. According to John Eliot Gardiner, it may have also served as an organ concerto for the new Silbermann organ in Dresden's Sophienkirche in 1725. Bach used the first movement of the concerto, in da capo form, as an extended instrumental introduction, assigning the solo part to the organ, the tutti to the strings and three oboes which he added for the cantata. The first vocal movement is an arioso, accompanied only by the continuo. Bach followed the careful wording of the poet by setting the lines from the following aria as a motto and conclusion of each thought as an arioso, the reflection which they frame as a secco recitative. The repeat of the essential line "Gott soll allein mein Herze haben" "acts like a rondo motif", according to Gardiner. In the aria, this line appears reminiscent of the arioso, but in reverse movement. As Gardiner observes: "It is a perfect example of Bach's skill in following admonitions by contemporary music theorists to 'grasp the sense of the text' with the goal of 'refined and text-related musical expression ... the true purpose of music'." The accompaniment of the virtuoso organ adds weight to the statement. Musicologist Julian Mincham interprets the "richly embroidered organ melody", which continues throughout the movement, as a "virtually continuous stream of goodness". A simple secco recitative leads to the second aria, which is again, like the Sinfonia, taken from the concerto, with the voice woven into the solo organ and the strings. According to Dürr, the aria is an example of "how a piece can gain rather than lose from its adaptation in the context of a new work". Another example is the Agnus Dei from Bach's Mass in B minor'. The text marks a farewell to love in the world: "Stirb in mir, Welt und alle deine Liebe". The music of the aria, marked "Siciliano" as the slow movement of the harpsichord concerto, has been regarded as a "farewell to worldly life", in "a mood of heart-stopping intensity", also as a mystic contemplation of a heavenly love. The aria has been compared in character to the aria of the repenting Peter "Erbarme dich" from Bach's St Matthew Passion. After the love of God has been expanded in great detail in five movements, the commandment to also love one's neighbour is expressed in a short recitative, leading to the chorale, which asks the Holy Spirit to assist in doing so, "so that we might love each other from our hearts and remain of one mind in peace".
